Blurry photo fixer

Hey there guys. I own a Sony Alfa a450 for the past 3yrs and I always had cool shots until some time last year. I started having some blurry photos(not all of them are blurry though) The other thing is im not a photographer but I love taking photos. So would it be that i'm not good or there is a problem with my camera? Anyone out there help me fix this problem please? Thank you.

Is your camera/lens auto-focus, fix-focus or manual focus?

Well thanks Beppi. I found the solution.